Mushroom penicillium: structure, properties, application. What is the structure of the mycelium penicilla Medicinal properties of moldy mushrooms fungus mucor penicillin

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Mucormycosis

Mucormycosis (Mucormycosic, mucorosis) - mold mycosis; caused by fungi of the genus Mysog; characterized, in addition to superficial lesions, changes in the respiratory system; sometimes tends to generalize the process. Mucormycosis is considered a rare human disease, but once it occurs, it can be potentially lethal.

Fungi of the family Mucoraceae (Phykomycetes) are found in all countries and are facultatively pathogenic for humans. Mycosis usually occurs as a result of an aerogenic infection or ingestion of spores with food; however, it often develops against the background of other diseases (tuberculosis, brucellosis, blood diseases, and especially diabetes with severe concomitant acidosis), etc. In addition to humans, diseases of this mycosis in animals are known - dogs, pigs, cattle, horses, guinea pigs.

The onset of the disease is often associated with the inhalation of fungal elements; subsequently develop mycotic bronchitis, less often - pneumonia ("pulmonary mucorosis"). With pneumomycosis, an autopsy revealed extensive caseous areas, around which growth of fibrous tissue was observed. The process also involves the lymph nodes, pleura, and sometimes the diaphragm. Microscopically: lesions are represented by necrotic tissue, surrounded by a small amount of stab leukocytes, plasma cells and eosinophils; giant cells are found. In necrotic tissue, and often in giant cells, large branching filaments of the mycelium of the fungus are found.

In addition to changes in the respiratory tract, as in aspergillosis, there are lesions in the area of the eye orbit, paranasal sinuses, followed by the germination of the fungus into the cranial cavity, which can cause damage to the membranes and substance of the brain (in the full sense of this concept - “a person has become moldy”). The development of mucormycotic meningitis is also possible as a result of the introduction of the fungus during spinal puncture. Also described are mucosal lesions of the stomach, intestines ("gastrointestinal mucorosis"), kidneys.

Sprouting the walls of arteries, veins and lymphatic vessels, the mycelium of the fungus forms "plexuses" in their lumen, resulting in thrombosis and heart attacks. With the generalization of the process, the course of the disease takes on a stormy character and quickly ends in death. Metastatic foci in generalized mucorosis are found in the internal organs and in the brain.

Rare manifestations include skin mucorosis (with redness, thickening, necrosis and the formation of ulcers with black crusts). Mold fungi can complicate various injuries, wounds, burn surfaces, trophic ulcers, which significantly aggravates their course.

In tissue sections, the causative agent of mucorosis is found in the form of an unsepted wide mycelium with a thickness of 4 to 20 microns. Sometimes at the ends of the mycelium, spherical thickenings filled with spores (sporangia) are visible. When tissue sections are stained with hematoxylin-eosin, the walls of the mycelium and spores are stained with hematoxylin, and the protoplasm is stained with eosin. Mushrooms are contoured more clearly when the background is repainted with thionin.

For the final diagnosis, microscopic examination of imprint smears and isolation of the fungus in pure culture is necessary. Tissue reaction in mucorosis is similar to changes in aspergillosis. In contrast to Aspergillus, the mycelium of Mucor is much thicker and not septate. However, despite these differences, the leading role in the identification of mucosal fungi belongs to the method of isolating them in pure culture. In some cases, lesions in mucorosis can be combined with processes caused by other molds or yeast-like fungi.

Penicilliosis

Penicilliosis is a fungal infection caused by fungi of the genus Penicillium. It is characterized by superficial lesions of the skin (including eczematous nature), mucous membranes, as well as bronchi and lungs. Penicilli, being saprophytes, are widespread in nature and are found in all countries. They become facultatively pathogenic with a sharp drop in the resistance of the macroorganism.

Damage to the internal organs is rare (for example, in HIV-infected people). Psoriasiform changes, onychia, paronychia (for example, in people working with fruits - oranges, etc.), nasal granulomas, otomycosis were noted. Bronchopneumonia and chronic bronchitis (without a characteristic clinical picture), unsuccessfully treated with conventional antibiotics; during examination, penicilli were found in sputum (often hemorrhagic).

In bronchopulmonary lesions caused by these fungi, exudate with an admixture of a significant amount of leukocytes, destruction of the epithelial and muscle layers were detected in the lumen of the bronchi. Cases of penicilliosis of the external auditory canal, deep lesions of the muscles of the perineum and gluteal region are described; reported penicillin cystitis, which simulated urolithiasis.

In tissue sections, the pathogen is found in the form of “felt-like” threads, clusters of spores; mycelium has a thickness of up to 4 microns; sometimes at the ends of it thickenings clearly protrude, from which chains of spores depart, resembling the figure of a brush. When staining tissue sections with hematoxylin-eosin, the walls and protoplasm of spores and mycelium are intensively stained with hematoxylin. The tissue reaction in penicilliosis is similar to that in lesions caused by other fungi.

Treatment of mold mycoses

The treatment of mold mycoses is complex and depends on the type of pathogen, the characteristics of the changes caused by it in the body, and the severity of the process. Antimycotic therapy should be carried out along with active treatment of the underlying (main) disease. Traditionally and with success, iodine preparations are prescribed - a 50% solution of potassium iodide orally, starting with 3-5 drops. 3 r / day (in milk or meat broth); there was a recommendation to administer intravenously 10% sodium iodide solution 5 ml for 1.5-2 months.

It should be borne in mind that iodides have a hypocoagulable effect, which is undesirable in case of lung lesions (the tendency of patients to hemoptysis). Antimycotics are used: amphotericin B with a rapid increase in dose from 0.25 to 0.8-1 mg / kg 1 r / day or every other day to a course dose of 2-2.5 g (with mucorosis - 3.0 g). In invasive pulmonary and extrapulmonary aspergillosis, a combination of amphotericin B and rifampicin (orally, 600 mg 1 r / day) is effective.

Amphotericin B is also used by inhalation in 5 ml of 5% buffer solution or 0.25% solution of novocaine, isotonic sodium chloride solution - in increasing doses (12500-25000-50000 units) with the addition of bronchodilators (I.P. Zamotaev, 1993). Inhalations are carried out 2 r / day (2 weeks). Amphotericin B can be replaced by a liposomal form - "Ambiz" at 3-5 mg / kg / day, 2-4 weeks (the dose increases with brain damage). Aerosols of 0.1% solution of gentian violet in propylene glycol or inhalation of ethyl iodide were recommended (Nekachalov-Margolin scheme).

Of the other antimycotics, pimafucin, nystatin, levorin in large doses (orally and in the form of inhalation of sodium salts), amphoglucamine 200,000-500,000 IU 2 r / day, mycoheptin, nizoral are used. Certain hopes are associated with the use of orungal 100-200 mg 1-2 r / day, 2-5 months. With aspergilloma (lung, paranasal sinuses), the effectiveness of antimycotics has not been proven, although orungal sometimes improves; the means of choice is surgery in combination with antifungal agents.

Taking into account the allergic and mycotoxic components, desensitizing (antihistamines, sodium thiosulfate, hexaethylenetetramine in a vein), detoxification therapy, immunocorrectors, interferon inducers (under the control of an immunogram), large doses of vitamins are necessary. According to indications, bronchodilators, secretolytic, cardiac drugs are used. In ABPA, corticosteroids in combination with antimycotics (orungal, nizoral) are considered the treatment of choice.

It is recommended to prescribe Lamisil 250 mg 2 r / day for a long time - up to 9-11 months. The possibility of using Diflucan in allergic aspergillosis is discussed (Congress "Clinical Dermatology 2000", Singapore, 1998). Desensitization with aspergillin or aslergillus vaccine should be performed.

Local treatment is prescribed for a superficial process. It includes aniline dyes, ointments, creams, aerosols with antimycotics, which are also advisable to be administered by phonophoresis.

Kulaga V.V., Romanenko I.M., Afonin S.L., Kulaga S.M.

In the entire history of mankind, there was no medicine that would save as many people from death as penicillin. It got its name from its progenitor, the fungus Penicillium, which floats in the air in the form of spores. We tell what happened in Fleming's laboratory and how events developed further.

Homeland - England

Humanity owes the discovery of penicillin to the Scottish biochemist Alexander Fleming. Although, of course, the fact that Fleming came across the properties of mold was natural. He went to this discovery for years.

During the First World War, Fleming served as a military doctor and could not accept the fact that the wounded after a successful operation still died - from the onset of gangrene or sepsis. Fleming began to look for a means to prevent such injustice.

In 1918, Fleming returned to London to the bacteriological laboratory of St. Mary's Hospital, where he worked from 1906 until his death. In 1922 came the first success, very similar to the story that led to the discovery of penicillin six years later.

A cold Fleming, who had just placed another culture of Micrococcus lysodeicticus bacteria in the so-called Petri dish, a wide glass cylinder with low walls and a lid, suddenly sneezed. A few days later, he opened the cup and found that the bacteria had died in some places. Apparently - in those where the mucus from his nose got when he sneezed.

Fleming began to check. And as a result, lysozyme was discovered - a natural enzyme in the mucus of humans, animals and, as it turned out later, some plants. It destroys the walls of bacteria and dissolves them, but it is harmless to healthy tissues. It is no coincidence that dogs lick their wounds - this way they reduce the risk of inflammation.

After each experiment, Petri dishes were supposed to be sterilized. Fleming, on the other hand, did not have the habit of throwing away cultures and washing laboratory glassware immediately after the experiment. Usually he was engaged in this unpleasant work when two or three dozen cups accumulated on the work table. First, he examined the cups.

“As soon as you open a cup of culture, you are in for trouble,” Fleming recalled. “Something will definitely come out of the air.” And one day, when he was studying influenza, a mold was found in one of the Petri dishes, which, to the scientist’s surprise, dissolved the seeded culture - Staphylococcus aureus colonies, and instead of a yellow cloudy mass, drops similar to dew were seen.

To test his hypothesis about the bactericidal effect of mold, Fleming transplanted a few spores from his bowl into a nutrient broth in a flask and left them to germinate at room temperature.

The surface was covered with a thick felt corrugated mass. It was originally white, then turned green, and finally turned black. At first, the broth remained clear. A few days later, he acquired a very intense yellow color, having developed some special substance, which Fleming was unable to obtain in its pure form, since it turned out to be very unstable. Fleming called the yellow substance secreted by the fungus penicillin.

It turned out that even when diluted by 500-800 times, the culture liquid inhibited the growth of staphylococci and some other bacteria. Thus, an exceptionally strong antagonistic effect of this type of fungus on certain bacteria has been proven.

It was found that penicillin suppressed to a greater or lesser extent the growth of not only staphylococci, but also streptococci, pneumococci, gonococci, diphtheria bacillus and anthrax bacilli, but did not act on Escherichia coli, typhoid bacillus and pathogens of influenza, paratyphoid, cholera. An extremely important discovery was the absence of a harmful effect of penicillin on human leukocytes, even at doses many times higher than the dose that is detrimental to staphylococci. This meant that penicillin was harmless to humans.

Production - America

The next step was taken in 1938 by Oxford University professor, pathologist and biochemist Howard Flory, who brought Ernst Boris Cheyne on board. Cheyne graduated in chemistry in Germany. When the Nazis came to power, Cheyne, being a Jew and a supporter of the left, emigrated to England.

Ernst Chain continued Fleming's research. He was able to obtain crude penicillin in quantities sufficient for the first biological tests, first on animals, and then in the clinic. After a year of agonizing experiments to isolate and purify the product of capricious mushrooms, the first 100 mg of pure penicillin was obtained. The first patient (a policeman with blood poisoning) could not be saved - there was not enough accumulated stock of penicillin. The antibiotic was rapidly excreted by the kidneys.

Chain attracted other specialists to work: bacteriologists, chemists, doctors. The so-called Oxford Group was formed.

By this time, World War II had begun. In the summer of 1940, Britain was in danger of being invaded. The Oxford group decides to hide the mold spores by soaking the broth in the linings of their jackets and pockets. Cheyne said: "If I am killed, the first thing to do is grab my jacket." In 1941, for the first time in history, a 15-year-old teenager was saved from death with blood poisoning.

However, in warring England, it was not possible to establish mass production of penicillin. In the summer of 1941, the head of the group, pharmacologist Howard Flory, went to improve the technology in the United States. On the extract of American corn, the yield of penicillin increased 20 times. Then they decided to look for new strains of mold, more productive than Penicillium notatum, which had once flown in Fleming's window. Mold samples from all over the world began to be sent to the American laboratory. They hired a girl, Mary Hunt, who bought all the moldy products in the market. And one day, Moldy Mary brings a rotten melon from the market, in which they find a productive strain of P. chrysogenum.

By this time, Flory managed to convince the American government and industrialists of the need to produce the first antibiotic. In 1943, industrial production of penicillin began for the first time. The technology for the mass production of penicillin, which immediately received a second name - "the drug of the century", was transferred to the enterprises of Pfizer and Merck. In 1945, the production of pharmacopoeial penicillin of high activity was 15 tons per year, in 1950 - 195 tons.

In 1941, the USSR received secret information that a powerful antimicrobial drug based on some type of fungus of the genus Penicillium was being created in England. In the Soviet Union, work began immediately in this direction, and already in 1942, the Soviet microbiologist Zinaida Yermolyeva obtained penicillin from the mold Penicillium Crustosum, taken from the wall of one of the bomb shelters in Moscow. In 1944, Ermolyeva, after much observation and research, decided to test her drug on the wounded. Her penicillin was a miracle for field doctors and a saving chance for many wounded soldiers.

Undoubtedly, the discovery and work of Yermolyeva is no less significant than the work of Flory and Cheyne. They saved many lives and made it possible to produce penicillin, so necessary for the front. However, the Soviet drug was obtained in an artisanal way in quantities that did not at all correspond to the needs of domestic health care.

In 1947, a semi-factory installation was created at the All-Union Scientific Research Chemical-Pharmaceutical Institute (VNIHFI). This technology, on an enlarged scale, formed the basis of the first penicillin plants built in Moscow and Riga. This produced a yellow amorphous product of low activity, which also caused fever in patients. At the same time, penicillin, which came from abroad, did not give side effects.

The USSR could not buy technologies for the industrial production of penicillin: in the United States there was a ban on the sale of any technologies related to it. However, Ernst Chain, the author and owner of an English patent for obtaining penicillin of the required quality, offered his help to the Soviet Union. In September 1948, the commission of Soviet scientists, having completed their work, returned to their homeland. The results were formalized in the form of industrial regulations and successfully introduced into production at one of the Moscow factories.

At the 1945 Nobel Prize in Physiology or Medicine ceremony that Fleming, Florey, and Chain received for their discovery of penicillin and its curative effects, Fleming said: “They say I invented penicillin. But no man could invent it, because this substance was created by nature. I didn't invent penicillin, I just drew people's attention to it and gave it a name."

Comment on the article "Penicillin: how Fleming's discovery turned into an antibiotic"

And now, many years later, penicillins are produced in various forms and combinations, they are used to treat bacterial infections in pregnant women, which is very important. Without antibiotics in the modern world anywhere.

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Penicilli

Genus Penicillium ( Penicillium) belongs to the order Hyphomycetes ( Hyphomycetales) from the class of imperfect mushrooms ( Deuteromycota). The natural habitat of these fungi is the soil, they are often found on a wide variety of substrates, mainly of plant origin.

Even in the XV-XVI centuries. in folk medicine, green mold was used in the treatment of purulent wounds. In 1928, the English microbiologist Alexander Fleming noticed that penicillium, accidentally introduced into a staphylococcus culture, completely suppressed the growth of bacteria. These observations of Fleming formed the basis of the doctrine of antibiosis (antagonism between individual types of microorganisms). L. Pasteur, I.I. Mechnikov.

The antimicrobial effect of green mold is due to a special substance - penicillin, released by this fungus into the environment. In 1940, penicillin was obtained in its pure form by the English researchers G. Flory and E. Chain, and in 1942, independently of them, by Soviet scientists Z.V. Ermolyeva and T.I. Balezina. During World War II, penicillin saved the lives of hundreds of thousands of wounded. The demand for penicillin was so great that its production increased from a few million units in 1942 to 700 billion units in 1945.

Penicillin is used for pneumonia, sepsis, pustular skin diseases, tonsillitis, scarlet fever, diphtheria, rheumatism, syphilis, gonorrhea and other diseases caused by gram-positive bacteria.

The discovery of penicillin marked the beginning of the search for new antibiotics and sources of their production. With the discovery of antibiotics, it became possible to successfully treat almost all infectious diseases caused by microbes.

But green molds are successfully used not only in medicine. Of great importance are penicilli of the species P.roqueforti. In nature, they live in the soil. We are well acquainted with them from the group of cheeses characterized by “marbling”: Roquefort, whose homeland is France, Gorgonzola cheese from Northern Italy, Stilon cheese from England, etc. All these cheeses are characterized by a loose structure, a specific “mouldy » appearance (streaks and spots of bluish-green color) and characteristic aroma. P.roqueforti needs a small amount of oxygen, tolerates high concentrations of carbon dioxide.

In the preparation of soft French cheeses "Camembert", "Brie" and some others are used P. camamberti and P.caseicolum, which form a characteristic white “felt” coating on the surface of the cheese. under the influence of the enzymes of these mushrooms, the cheese acquires juiciness, oiliness, specific taste and aroma.

Aspergillus

Aspergillus, like penicilli, belong to the class of imperfect fungi. Their natural habitat is the upper soil horizons, especially in southern latitudes, where they are most often found on various substrates, mainly of plant origin. Most representatives of this genus are saprophytes, but there are also conditional pathogens of humans and animals, which, for example, in people with weakened immunity can cause diseases - aspergillosis.
mushroom species A. flavus and A.oryzae- the main components of the fungal community that develop on grains and seeds, mainly on rice, peas, soybeans, peanuts. They produce enzymes: amylases, lipases, proteinases, pectinases, cellulases, etc. That is why A.oryzae and related species have been used in the East for food purposes for many centuries. The alcohol industry in Japan and other countries of the East, in which rice starch must first be saccharified to make sake rice vodka, is entirely based on the enzymatic properties of this group of mushrooms. Traditional seiyu soy sauce, tuong soy rice sauce (Vietnam), miso soy bean soup dressing (Japan, China, Philippines) and other food products are made using aspergillus.
The ability to A.niger and other species of this group to the formation of citric, oxalic, gluconic, fumaric acids. In addition to the organic acids of Aspergillus, and in particular a.niger, are capable of synthesizing vitamins: biotin, thiamine, riboflavin, etc. This property of them finds industrial application.

Table 1. Properties of mushrooms

Mushroom-predator found in a piece of amber

Amber captures how an ancient predatory fungus ringed a nematode worm, possibly in order to eat it

German scientists from the Humboldt University of Berlin (Humboldt-Universität zu Berlin), led by Alexander Schmidt, discovered a piece of amber in a quarry in southwestern France, in which, presumably, a predatory fungus about 100 million years old and the remains of nematodes were preserved.

The discovery broke the previous record: the predatory mushroom found then was only 15-20 million years old. But not only this surprised the researchers. Usually predatory fungi live in the soil, and they have a very small chance of being "frozen" in amber (which is originally tree resin). Now scientists hope that this specimen will shed some light on how these strange creatures evolved.

Modern carnivorous fungi often trap in their sticky "webs" and rings (working like a lasso) very small nematode worms that feed on their surface. When the worm dies, the tissues of the fungus grow into it and digest it.

So far, scientists do not know how predatory fungi have changed throughout their history, and it is almost impossible to study this. Mushrooms lack a skeleton or shell, so when they die, nothing remains. That is why this discovery is so important for researchers.

Since the mushroom found has the same loops as modern representatives (about 10 micrometers in diameter), biologists conclude that such feeding behavior was characteristic of ancient representatives of predatory fungi.

Predatory mushrooms at your service

Have you ever come across a toothy boletus in the forest? Have you seen a butter dish armed with sharp claws?

Not? Then everything is correct. Forest mushrooms are peaceful people. Even the handsome fly agaric, which is notorious, is not going to attack anyone. It stands in a forest clearing, waiting for the animals. They say the moose love him very much. And the terrible pale grebe itself is frightened to death, tries to stay away from people, lurks in the forest more often. And it’s not her fault, but the trouble is that it looks a little like champignon.

And yet they exist, these strange predatory mushrooms, so unlike the familiar gifts of the forest.

First, a graceful worm appeared on the screen. Enlarged many times by shooting, he freely swam in the solution, bent, willingly posing. But some strange threads appeared in the corner of the frame. They slowly but surely crawled towards the worm. From the threads, processes departed, turned into hooks and loops. A whole network has already grown around the worm. He is still trying to free himself, struggling desperately, but the rings and loops are getting tighter and tighter. End.

Thus, Doctor of Biological Sciences Nissa Ashrafovna Mekhtieva began her report on predatory fungi at the All-Union Conference “Ways to Improve Microbiological Control of Harmful Insects and Plant Diseases” almost like a horror movie.

VINEGAR EEL AND OTHERS

The heroine of the film, the vinegar eel, is a harmless creature. He lives in fermented vinegar, does not interfere with anyone. Researchers like to use it as a model organism for various experiments. To do this, just drop a little vinegar into the starch paste. But her numerous brothers and sisters in the class of nematodes, or roundworms, are not like that.

I want to be understood correctly. I do not at all intend to cast a shadow on this whole class, which, in terms of the number of individuals, is the most numerous in the animal kingdom and second only to the class of insects in the number of species. Many of its representatives honestly work in remote corners of the Earth, sometimes in very difficult conditions, making an invaluable contribution to the cycle of substances in nature. These are worthy, respected inhabitants of water and land. Especially many nematodes live in the soil.

Take phytonematodes living in plant tissues. Previously, crop failures in potatoes and beets after several years of monoculture were attributed to "soil fatigue". It was only in our century that it was discovered that nematodes were to blame. The annual loss of world agricultural products from them is about 12%. In monetary terms, for the 20 major crops, this is $77 billion. And do not think that such a problem is only in developing countries with backward agricultural technology. For example, in the USA plant nematodes cause an annual loss of 5-8 billion dollars. And so now, compared with 1967, the cost of studying phytonematodes in the United States has increased eight times.

These tiny worms are harmful in fields, vegetable gardens and greenhouses. For example, cucumbers and tomatoes are tormented by the so-called gall nematodes, which form swellings on the roots.

ETERNAL FIGHT

To combat nematodes in greenhouses, the soil is steamed and a pesticide is introduced - some kind of nematicide, such as dazomet or heterophos. For retail sale to the population, we only allow one nematicide - thiazon 40%. It is recommended to apply it evenly into the soil (thoroughly mixing it at the same time to the depth of the arable layer). With a strong infection with gall nematodes, you have to change all the land in the greenhouse.

To get rid of nematodes in the fields, farmers have long used crop rotation. For example, after 5-7 years of potato mono-culture, lupine or other legumes are grown. It has also been noticed that some plants, such as radish and marigolds, scare away nematodes.

However, these measures do not give complete improvement of the soil.

More hope for breeders, for resistant varieties. Since the 1960s, many potato varieties resistant to nematodes have been bred in different countries. Alas, often their tubers turn out to be tasteless not only for nematodes, but also for us. So it happened, for example, with the Meta variety, bred by the Lithuanian Research Institute of Agriculture in conjunction with the All-Union Research Institute of Helminthology. K. I. Scriabin. Zoned in Lithuania, Belarus and several regions of the RSFSR, it does not find sales due to low taste.

Genetic engineering has also joined the fight against nematodes. Last summer, two US firms, Mycogen and Monsanto, signed an agreement to introduce a gene responsible for producing a toxin from the bacterium Bacillus turyngiensis into soybean, cotton, tomato, and potato plants. This toxin kills plant nematodes. It is believed that plants will protect themselves in this way.

Why is the fight against nematodes so difficult?

The fact is that over many centuries of evolution, nematodes have forged a very serious weapon - the ability to form cysts. The cyst is an old female stuffed with larvae. A sort of leather bag. Thanks to its strong shell, the cyst calmly endures all adversities - both steaming and chemical tillage. The cyst can be stored in the ground for decades. And the time will come - the larvae will come out of it and take on their own. But back to predatory mushrooms.

THE THIRD KINGDOM

Carl Linnaeus, the creator of the taxonomy of the living, attributed mushrooms to the plant kingdom. He had good reasons for this. Like plants, fungal cells are surrounded by a cellular membrane, and, Linnaeus believed, fungi, unlike animals, are incapable of active movement.

However, today experts distinguish mushrooms into a separate third kingdom, different from plants and animals. The number of species in it is huge. Many of them are hostile towards people: they cause human diseases. They do not spare both animals and plants, they spoil food, wood, textiles and other materials. But among the mushrooms there are those whom we can rightfully call friends. Among them are the heroes of my story. The English scientist C. L. Daddington titled his book about them: "Predatory mushrooms are the friends of man."

In science, they appear not so long ago, since the sixties of the last century. It was then that the famous Russian mycologist and phytopathologist, specialist in fungi and plant diseases Mikhail Stepanovich Voronin, examining the soil fungus Arthr under a microscope o botrys oligospora, carefully described and sketched hooks, loops and rings that no one had yet seen, which are abundantly formed on the threads and spores of the fungus. Alas, their appointment remained a mystery for many years.

Only in the 80s of the same 19th century, Wilhelm Zopf, a professor at the University of Halle, established that strange formations are nothing but hunting tools! Catching loops, rings and hooks are needed by predatory mushrooms in order to hunt nematodes that surpass them in strength and size.

Penicilliosis

Mushrooms of the genus Penicillium, abundantly present in the external environment, are one of the most frequent laboratory contaminants; the diagnosis of penicilliosis in patients can only be confirmed by examining a section of tissue for the presence of fungi. Without this study, the diagnosis is still in doubt, even with repeated receipt Penicillium from the sputum of patients with pulmonary pathology. When re-isolated fungi, investigators should determine the possible presence of other fungi, as well as the source of infection of the patient (inhalation or the presence of bronchiectasis). Often the association with bronchiectasis is due to the fact that the fungi may be without significant infection in the tissue. Also, the presence of fungi can be random and insignificant (not significant), for example, this applies to other saprophytes. Among fungi of the genus Penicillium only P. marneffei known as a primary pathogen of humans and animals. This species is unique among the mushrooms of this genus, because. has temperature dimorphism and a geographically limited distribution halo (Southeast Asia and part of the Far East).

In patients with acute leukemia and gastrointestinal candidiasis Penicillium commune was isolated from the lungs and brain tissue, where it had profuse growth with vascular invasion, thrombosis, and pulmonary infarction.

Huang and Harvis described 10 cases of penicilliosis, while five patients were practically healthy people, that is, they had no other pathology. The following species have been isolated Penicillium: P. crustareum, P. glaucum, P. bertai, P. bicolor, P. spinulosum. It is still unclear whether these fungi are the primary etiologic agent.

Gilliam and Vest observed significant cases of urinary tract involvement P. citrine. The patients had a fever, and also complained of sporadic pain in the right side, and urine was excreted with a developed thin mycelium. Pyelograms showed changes in the pelvis of the right kidney. During drainage catheterization, mycelial samples P. citrine were found only in the urine from the right ureter.

The scientific literature also describes 4 cases of endocarditis caused by fungi of the genus Penicillium. At the same time, in one case, fungi were isolated from a prosthetic valve and were identified as P. chrysogenum, in 3 cases - an unidentified Penicillium that caused endocarditis following valve implantation; P. chrysogenum and unidentified fungi of the genus Penicillium were isolated in post-traumatic endophthalmitis, P. citrine and P.expansum- with mycotic keratitis; unidentified species Penicillium were the cause of systemic diseases in 2 immunocompromised patients and P. decumbens were identified in the case of fungemia in AIDS (patients were treated with amphotericin B).

Penicillium like an allergen.

Mushrooms of the genera are often associated with allergic diseases. Aspergillus, Penicillium, Botrynis, Monilia, Trichoderma. Colonies Penicillium green color can often be seen on things stored in the basement. Mushrooms Penicillium present in Camembert and Roquefort cheeses and may cause clinical symptoms in sensitized individuals.

Mushrooms of the genera are the most allergenic Alternaria, Aspergillus, Cladosporuim and Penicillium. The incidence of sensitization to fungi in patients with bronchial asthma approaches 25%. At the same time, inhalation sensitivity to Penicillius spp. does not increase the risk of adverse reactions to penicillins.

It has been established that house plants cause only a slight increase in the number of spores of fungi such as Cladosporium, Penicillium, Alternaria and Epicoccum in residential areas.

penicillosis due to Penicillium marneffei .

Penicilliosis marneffei- a disease caused by a fungus Penicillium marneffei(Segretain, 1959), first isolated from the liver of a bamboo rat; widespread in Southeast Asia. Segretain, who described the fungus, was infected with the fungus after accidentally contacting his finger with the isolated culture. In the scientific literature (from 1959 to 1990), about 30 cases of the disease in humans caused by Penicillium marneffei, mainly in the East and Southeast Asia. The first case of penicilliosis was noted in an American priest with lymphogranulomatosis, who lives in North Carolina (USA), but worked for some time in Vietnam.

Jayanetra et al described 5 cases (3 fatal) of disseminated penicilliosis in Thailand. In one case, the patient lived in Florida (USA), but traveled a lot in the Far East. Foreign authors also reported 9 cases of a disseminated process (in 1985) in Huang He Province (China) on the border with Vietnam, one case in Hong Kong. In other works, the authors describe cases of penicillosis in four HIV-infected patients from Europe and the United States, three of whom traveled to Southeast Asia, the location of the fourth was not reported.

We observed 30 patients with penicilliosis aged from 3 months to 71 years; seven of whom worked as farmers; three are children under the age of 10. Prior to the diagnosis of penicilliosis, four patients received corticosteroid therapy for SLE, hematological disorders, and kidney transplantation. Other patients had myelogranulomatosis. Clinical manifestations of penicilliosis were fever, weight loss, anemia, which in the absence of therapy inevitably led to death. The organs involved in the disseminated process are presented in the table.

There are certain errors in the presented table, since the finger was damaged by the contact of the researcher with the culture, and in case of damage to the nasopharynx, the culture was not detected at all, therefore, the diagnosis was made according to the histological examination of the material of nasopharyngeal carcinoma. Lymphadenitis was found in many places, some nodes ulcerated, suppurated or drained through the formed fistulas. Skin lesions also tended to be multiplicity, erythematous, in some patients deep subcutaneous abscesses were observed (sometimes they were drained with pus). Osteomyelitic lesions were either single or multiple, involving various bones and presenting as cold abscesses, spreading skin lesions, or purulent arthritis of adjacent joints. Hepatosplenomegaly was noted in many cases of disseminated disease (including three children), but jaundice was not observed in any case. Radiographs of patients with lung disease showed localized and patchy infiltrates with or without abscesses or empyema; one patient with AIDS had a diffuse infiltrate. In one patient, the radiograph was normal, but bronchoscopy showed positive fungus inoculations. One of the three patients (with involvement of the colon) developed peritonitis from perforation of a lesion in the sigmoid colon. In a laboratory study - blood leukocytes are normal or moderately elevated. Thrombocytopenia or leukopenia was not noted among those who did not have predisposing diseases. Diagnosis was made in life by culture or histopathology of skin, bone, or liver lesions. Bone marrow culture was positive in four patients, some had a positive blood culture (the sensitivity of some culture methods cannot be assessed from the articles). Other types Penicillium not determined, while it was not entirely clear whether Penicillium marneffei found in an endemic area as a laboratory contaminant or commensal in an injured respiratory tract.

In the scientific literature, amphotericin B is presented as the drug of choice for penicillosis. High mortality during therapy indicates the need for rapid diagnosis, relapses after treatment indicate the need for a long (several weeks) course of therapy. The pathogen was sensitive to flucytosine; a number of patients had positive dynamics with the combination of flucytosine and amphotericin B. One patient with AIDS noted an improvement in the condition when using ketoconazole (400 mg per day); it is likely that this patient could only have bronchial colonization and not infection. The histopathological picture of these lesions (in contrast to the neutrophilic reaction in the skin and bones) is similar to histoplasmosis, ie. granulomatous inflammation, necrosis, and yeast-like cells within phagocytes. Suppurative follicles present as a pyogranuloma with necrotic areas containing yeast-like fungi surrounded by epithelioid cells, lymphocytes, plasma cells, and giant cells. Without special stains, lesions can be easily confused with tuberculosis, cocidioidomycosis, parkoccidioidomycosis, or histoplasmosis. Fortunately the definition Penicillium marneffei with special coloring does not cause difficulties for a trained specialist.

Yeast-like cells Penicillium marneffei- oval (elliptical), 3 microns in diameter, attached inside heliocytes or scattered around the tissue; elongated cells - up to 8 microns long with a septum, often curved like a sausage. Cells Penicillium marneffei do not stain with hematoxylin-eosin, according to PAS reaction and GMS. Unlike Histoplasma capsulatum, rare cells Penicillium marneffei binuclear in tissue.

Laboratory diagnostics

On microscopic examination, the histopathological material is stained with GSM or PAS, and the presence of yeast-like cells with a septum confirms the diagnosis. culture Penicillium marneffei, isolated from sputum, from the contents of lung abscesses or skin nodules, is incubated on Sabouraud's medium with antibacterial antibiotics at 25 and 37 ° C with a demonstration of thermal dimorphism.

Mycology.

According to the systematics of Raper and Thom, Penicillium marneffei classified into a group Asynmetrica divanicata and beforehand in Asynmetrica fasciculata by Ramirez.

Pitt re-identified isolate Penicillium marneffei(ATCC 24100) obtained from the first case of human infection, as P. primulinium. Sekhom et al. nevertheless showed that isolates Penicillium marneffei containing ATCC are antigenically distinct from isolates P. primulinium. P. marneffei grew rapidly on Sabouraud agar and produced greyish, soluble brown-red pigmented colonies (elongated, 3.5 to 4 cm in diameter) which at 25°C turned blue-green after 2 weeks, like mature conidiophores. Conidiophores (smooth) support terminal vesicles of 3 to 5 metulae, each containing several phialides (9 to 11 x 2.5 µm), which in turn support smooth, round-semicircular (2 to 3 µm in diameter) conidia in a chain. At a temperature of 37 o C in vitro P. marneffei produce small, white-brown-red, dry, yeast-like colonies with smooth surfaces. The transition of the mycelium to the yeast form becomes evident within 14 days during incubation at 37°C. At an early stage of transformation, the mycelial cells become shorter, often septate. Other cells are oval, almost elliptical, 2 to 6 µm in diameter. Although the source of P. marneffei is unknown, the fungus was first isolated in the Huang He (an endemic region of penicillosis in China) from some pairs of bamboo rats, which are the main vector of this infection. More than 90% of these animals caught in the Yellow River were found to have P. marneffei in internal organs without any major lesions (Kwon-Chung, 1992).

Treatment. See the "" section on the Russian Medical Server.

Fungi of the genus Penicillium are one of the most common in nature, there are about 1000 species. Morphologically, the genus Penicillium is characterized by multicellular septate mycelium. The fruiting body looks like a brush. It is formed by sterigmata located at the end of a multicellular conidiophore; fuzzy-shaped rows of conidia depart from the sterigmata. There are four types of structure of brushes: one-toothed, two-toothed, asymmetrical and symmetrical. In addition to conidial forms of sporulation, penicilli also have marsupial sporulation.
Penicilli are aerobes; can develop on a wide variety of nutrient media, the acidity of the medium can be pH from 3.0 to 8.0. The temperature optimum ranges from 20 to 37 °.

Penicilli are less likely to cause disease than aspergillus. Of the lesions of the visceral organs of Giordano, a case of pulmonary pseudotuberculosis caused by Penicillium glaucum is described. Chronic nail infections are caused by Penicillium brevicaule (Brumpt and Langeron).

Also described superficial skin lesions in the form of epidermodermatitis, as well as deeper layers of the skin of a gummy nature, which are accompanied by regional lymphadenitis. The causative agent of the skin disease Carate, common in Central America, is also a fungus of the genus Penicillium. Cases of damage by this fungus to the paranasal sinuses are described (V. Ya. Kunelskaya, Motta).

All mushrooms that do not have a sexual way breeding, are assigned to an artificially created and phylogenetically unrelated group of imperfect fungi - Fungi imperfecti. This group includes fungi that cause diseases of the skin of humans and animals, known as dermatophytes or dermatomycetes.

To the group of imperfect fungi include radiant fungi - actinomycetes. In terms of their morphological and biological properties, they occupy an intermediate position between fungi and bacteria, since in terms of the structure of their mycelium they are close, on the one hand, to lower unicellular molds, and on the other, to bacteria (N. A. Krasilnikov). The entire branching mycelium of radiant fungi consists of a single cell. Actinomycetes reproduce with the help of opidia - segments that are formed as a result of the breakdown of the terminal filaments into separate segments. Actinomycetes got their name due to the characteristic radiant structure of their colonies in liquid media and the formation of peculiar grains - drusen, which also have a radiant structure under a microscope. The fungus develops slowly. The optimum temperature for growth is 35-37°; pH 6.8. Some species are anaerobes, others are obligate aerobes.

Actinomycotic diseases characterized by the formation of abscesses with fistulous passages. According to Gill, in 56% of all manifestations of actinomycosis in humans, localization is cervicofacial. Actinomycosis of the lungs, chest organs, according to G. O. Suteev, ranks second in frequency. Actinomycosis of the digestive tract, liver, spleen, as well as bones and joints are described.

All skin defeat, according to G. O. Suteev, are divided into gummy-nodular, ulcerative and tuberculous-pustular. Actinomycosis tonsillitis with keratinization of the mucosal epithelium, as well as actinomycosis lesions of the maxillary sinuses and cells of the ethmoid labyrinth have been described (O. B. Minsker and T. G. Robustova, Motta, Gill). A large group of yeast-like fungi also belongs to imperfect fungi.

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